1. Field of the Invention
The invention relates generally to a direct memory access and, more particularly, to using one processor to set up a direct memory access for another processor.
2. Description of the Related Art
In a computer system, data is transferred from one memory location to another memory location using load and store instructions or using direct memory access controller (DMAC). Load and store instructions have a very long latency. That is, a processor in the computer system should wait for a large amount of data to transfer before working on the load and store instruction. At first, data needs to be read from one memory location into a processor's registers. Then, the data will be transmitted to another memory location from the processor's registers.
DMAC provides a mechanism to move data from a memory location to another memory location without involvement of a processor. In a prior art system, the processor has to set up the DMAC before the DMAC can perform the data transfer on its own. Once the DMAC is set up, the processor can perform other tasks while the DMAC takes care of the data transfer.
A multi-processor system may have one or more special processors dedicated to important tasks and one or more general-purpose processors. In such a multi-processor system, a special processor may have its own DMAC to set up. In that case, the special processor ends up spending its valuable time on setting up the DMAC. This may adversely affect the entire performance of the multi-processor system, because the special processor cannot perform its own special tasks while it is setting up the DMAC.
Therefore, a need exists for a system and method for improving performance of a computer system by freeing particular processor(s) from the job of setting up the DMAC.